460 CONSERVATIVE ORGANS. j^LECT. IX. 



of branches and leaves, and sometimes flowers, 

 and never separating from the parent *. 



Gems are found on all trees and shrubs in 

 temperate climates. In the majority of instances 

 they are visible from the first, in which case they 

 are axillary, that is, seated in the axillae of the 

 leaves, or the angle which the upper part of the 

 footstalk of the leaf makes with the surface of the 

 stem ; and terminal, or at the extremities of the 

 branches : but in some instances, for example, 

 the Sumachs, Rhus, and the Planes, Platanus, 

 they are latent ; being hid within the base of the 

 footstalk, and never seen until the fall of the 

 leaf. In the marginal cut, a. repre- 

 sents the footstalk of a leaf of the 

 Oriental Plane, Platanus orienfalis, 

 split longitudinally to show the ca- 

 yity b. in which is seated c., the 

 gem. Gems are, however, some- 

 times protruded from the trunk, 

 long after it has ceased to produce 



* The above definition is a modification of that of Gaertner, 

 who thus defines the gem, " a compound subulate or pyramidal 

 " germ, with manifest herbaceous leaflets, containing the rudi- 

 " ments of branches, and never separating from the mother." 

 Linnaeus's definition is less correct, " Gemma est hybernaculum 

 " caudici adscendenti insidens. Constat vel stipulis, vel 

 " petiolis, vel foliorum rudimentis, vel squamis corticalibus/' 

 Phil. Bot. 85, 2. 



